Fireball Models for Flares in AE Aquarii

We examine the flaring behaviour of the cataclysmic variable AE~Aqr in the context of the `magnetic propeller' model for this system. The flares are thought to arise from collisions between high density regions in the material expelled from the system after interaction with the rapidly rotating magnetosphere of the white dwarf. We calculate the first quantitative models for the flaring and calculate the time-dependent emergent optical spectra from the resulting hot, expanding ball of gas. We compare the results under different assumptions to observations and derive values for the mass, lengthscale and temperature of the material involved in the flare. We see that the fits suggest that the secondary star in this system has Population II composition.